The present invention relates to automatic guided vehicle (AGV) control systems and, more particularly, to an AGV control system incorporating a replaceable PROM which contains instructions for AGV operation.
In the field of material handling, most commonly in a warehouse environment, many articles must be stored in inventory and, an indefinite time later, retrieved for use. The larger the warehouse facility, the greater the number of objects that can be stored.
Moreover, large warehouse facilities require a great amount of geographical space. Not only are modern warehouses spread over a significant distance, but their height allows a great number of objects to be stacked for storage one above the other.
When the warehouse is large, it becomes burdensome to move material from one part (e.g., the port of entry) to another part thereof (e.g., a storage bin).
It has been found that guided vehicles moving over a buried inductive cable can perform many of the functions that humans perform without the requirement of lighting, heating, ventilation and air conditioning that would normally be required for a pleasant human work environment. Moreover, AGVs can be relied upon to operate continuously 24 hours per day. This advantage of performance over human laborers results in greater efficiency for warehouse facilities.
The most valuable AGVs are those that require the least supervision. That is, an intelligent, autonomous AGV can be used with greater flexibility than can an AGV that is dependent upon an external central processing unit for operation. Clearly, autonomous AGVs are capable of performing a great number of tasks.
Heretofore, when the floor plan of a storage facility was remodeled or the facility was itself changed, an AGV that was programmed to operate in accordance with the old facility's map had to be rebuilt or discarded entirely. Moreover, any group of lesser activities, such as traffic control protocol, pathfinding operations, speed control and the like also required extensive remodeling of the AGV.
Heretofore, AGV systems have been unreliable. Often these systems caused more problems than they were designed to eliminate. AGV systems have been found to require human intervention, a condition they were to alleviate.
These drawbacks have severely hurt the industry (Ailing robot industry is turning to services, John Holusha, Business Section, New York Times, Page D1, Feb. 14, 1989).